Mold for manufacturing cement pipe.



.|. G. ZWICKER.

MOLD FOR MANUFACTURING CEMENT PIPE.

APPLICATION man JULY 9. 1910. RENEwED Nov. 10. 191s.

1 ,1 60,235. Patented Nov. 16, 1915.

COLUMBIA .PLANocR/PH to.. WASHINaToN, n. c.

i perities, and pores or intersticial recesseson dil .To all whom it may concern.' 'Y

'mold to the introductionl therein ing drawings; in which:

JULrus s. zwio'xnia,

F MEXICO, MEXICO.

l i MOLD non MANUFACTURING CEMENT rirn.'

. Application fledvJ'uly 9, 1910, Serial No. 571,231.

Be it knownthat I, JULis lGro'iiois Zwioiinn, citizen of the United States, resid-` ingY at the city kof Mexico, -Mexico, haveinvented certain new and useful Improvements, in vMolds forv Manufacturing Cement Pipe, of which thefollowing is a specification.

`My invention relates -to'a mold for formconcrete -or similar ma# ing pipes of cement, terial which may be poured into the mold in a .plastic state and 'becomes hard and tenacious when dry, which pipes are threaded at both ends, being similar to the pipes withv threaded ends covered by myk application Serial No. 522,442, filed October '13, 1909, but Ydiffering from these inv that their inner and outer surfaces are made smooth and of a very Aclose grained texture somewhat resem.

bling glazed earthen ware pipes. These surfaces being made of pure cement which incases the concrete'shell of the pipe proper necessarily require an adaptation of the of two separate materials; hence require a doublewalled mold. Pipes thus lined within and without withv a compact, Vhomogeneousmaterial -forming a smoothsurface, offer many advantages compared to those having astheir inner and outer walls. For the interior4 the reduction in frictional resistance to the passage` of liquids is an improvement apparent to the layman. In addition to this when rough-lined pipe are used for sewersl I or drainage out falls,

. solid material lodges in the recesses and much of the entrained crannies, small though they be, or against the internally projecting' asperities, where they form nuclei for and give foothold to constantly increasing deposits which are sure yV to materially v.reduce the4 effective area of passage while correspondingly increasing thejfrictional resistance; `As'to the outer surface a smooth, compact-facing prolongs thevlife, improves the appearancev and in many cases facilitates the handling of such conduits. v-

To obtain these results I'use a double-A walled mold, represented in the accompany- Figure 1, is a vertical diametrical section vof the mold as it appears when ready for pouring in the conrcete; Fig. 2, a horizontal section of Fig. 1 taken on line X-X,show ing the restoring and collapsingl device for Specication of Letters Patent.

Y Patented Nov. 16, 1915. Renewed November 10, 1913. SerialNo. 800,229.

inner shell intop plan view; Fig.- 3, a detail v showing in .top plan view the device for restoring and collapsingv inner shell of mold;

Fig. 4, a side `elevation of restoring and col-v lapsing frame; Fig. 5, a vertical diametrical ysection of the main mold, or mold proper filled withcementslined concrete, the auxiliary or surfacing shells having been withdrawn, and the pipe covered to protect it while becoming hard, and Fig. 6`is a horizontal section of the mold filled with concrete partly set, `showing vthe* inner shell after collapsing.

As a foundation orjsupport I prefer the ground or the floorv of the molding yard.V

On this the base-ring 2 is laid the annular bead 2@t sinkinginto the ground. This ring is virtually a` modification of the female matrix described in my United States appli'- cation Serial No. 522,441, filed October 13, 1909, being made of plaster of Paris as before. The matrix or thread-forming part proper 3, projects upwardly from the basering part proper, which extends inwardly for a short distance, ledge-y 4, and outwardly for a. greater distance, forming the ledge or flange 5, the outer face'of which has an off-set or jog.

making annular lledge 6. Shell 7, made of thin sheet metal slit vertically at 8. is next set upon ledge 4. A batten 9 extending the full height of shell 7, is secured to the inside of each side of the slit 8,'by screws or nails 9?, the meeting sides of said battens being chamfered so that when they come together they will form a prism of wedge-shaped horizontal section 10,the base of which is on the inside and when spread apart. a prism having a rhomboidal section 10a. These two' battens form the front or outer vertical members of a pairof equal frames, extending inwardly as far as the center of the inner shell where their rear upright members 12v forming an annular at their 'free outer ends, as shown in Fig. 3.

curve to bear against the smooth' faces 'of the 'opposite cross strips the-short' eurve Working in the setI of'l'r'erbsj as bearings or' pivots, Vwill c'a'use the two frames'to open out,

Fifgrpt shows the position of the 'canrbar after it has -been turned out ofthe-*reston- -in-'g position.v From this 'it will 'be seen that upon turning it towardt'lie diameter of the shell parallel to `its majorAv 'aXi's the short curve presses'against the 'straight inner `laces Yof the cross-strips, forcing the jaws'apa'rt.

W'hen the j aws are opened the battens 9Y with Ythem the 'edge'of the slit in shell 7, the width ol3 opening 4of the being such that the shell 'is restored to its true geometrical figure, when vertical drstance-battenll of rh'ombo'idal section i's inserted in the opening of the saine section,-

now formed between the inner sides of battens 9, 9. To the shorter 'or outer lace 'ofthe distance-battena `'curved strip of sheet iron is secured which justcoinpletes the figure of ithe inner shell 7 The distance-batten `is kept in position by bearing against `the sides ofthe three springs T6. n'expan'ding `this shell 'the Ybottoni 'part is pressed tightly against the inner face of matrix 3, whereby l it is securely held in place; which is iin- Y drical bell,

portant as in withdrawing the auxiliary or inner surfacing 'shellpit will tend 'to pull themain inner vshe-ll with fit. j 1 p p A'turned 'disk l`9,ha'vinrg"an eye-bolt 19a. for'handli'n'g it, is pressed'into 'the mouth of shell 7, the tlower part of its edgesffl'arinfg upward as far as a jog or yoffset 'which rests on `the upper edge of shell 7, the' upperpart of the disk entendi-ng outv'var'd lor a quarter 'of an inch or thereabouft, to keep 'the' iliary shell'at the proper distancefrom the inner shell,rw hile ther inner pf thefjn'og keeps the vmouth of shell 7 extended to its full or exact diameter. l

vAuxiliary or -surfacingshell ZOPs arcylinabout one 'quarter inch greater in diameter than the inner shellf?.V The lcyl-- inder yis perforated throughout its 'height with small holes .pitched closely together.'

I A hollow cone 2l crowns the cylinder' 20 Fand supports at its apex han'd-wheel.22.` This surfaoing cone is slipped 'over the 1outside of; shell 7 forming a cylindrical space 20a about one yquarter inch 'wide between the moldshell proper. 'and the -surfaciing :'shell,

which latter rests" 'on the top of anahrix 13.

vInto this space 'a cement paste is forced cross-strip `vll of. 'oneA through the perforations, being pressed against the holes with altrowel, until said sp'ac'e fi'scbrnpletely iilled. :The outer shellv23,"is ai cylindrical shell lcponcentric withl shell 7, having a verticalslit 24,4 on each side of which a vertical ang gle iron 2'5 is riveted to theoutside Vof the shell, `provided with A'bolts Yand, nuts Vto* enable the twor partsv of theshell to -be drawn ,Y

together. ThisV i'sfsetv upon the ledge 6 formedpinbase-ring 2, andz isfthendrawn vto'g'jether against the vertical edge offlange sp'aceK 27 between Vthe outer and inner surf` facing shells, filling. it t'o within a short 'distance 'from 'the top. *While theV concrete is still plastic,- inner su'racing` shell 20 fis turned hack and Vforth its axis by .handwheel4 2Q, this oscillatory movementnbeiig continued while the shell isr being Y'drawn upward, allowing the cement paste that was in Yspace 20a* to unite wi'th the concrete,

forming onebojdy therewith.. This pro-A vides the inner surface 'of 'the ypip-e with a cOm'PICt, 'smooth lining of: pure cement.

Now outer surfacing shell '25a is withdrawn in the 'same beaded riinro'f funnel '26 `serving''as ahaird hold vfor pullingr upward and turning'the strainer'likeshell to andiffr'o'. In this' op'- eration, 'owing 'tothe tight lit hetween'the two cylindrical walls, and the oscillatory move'I'ieiit,v a ysaiiiicient'quantity of cement will be drawn from the concrete to the sunV face to `Cause the'outer layer ofthe finished` pipe 'to' be practically pure cement. At the same time the bubbles of air which form onv the inner surface of the outer r'shell afre'burst, the "air being drawn out with the shell. From 'the combinedfeii'ects-a smooth, closegrai'ned outer .surface results, made of a homogeneous material-a result which: thus far has never beenjattained with pipes made of concrete-` VNext the male matrix 28 isi-1'1-V serted, thewflaringmouth 29'V of' the outer shell facilitating its introduction. This"masv triX, made of plaster'o'f Paris, Ydiii'ers from Y the onefof inyv previously mentioned application y,Serial No. 522,441 only in having 'its upper; portion ,'Iln'a'd'e of an increased diameter forming aledge ll30, :which 'rests on Lvtop of the -r'ii'iter shell, and prevents the matrix from 'sinking' into the s'otfc'oncrete, whereby the threads would ycorne into the wrong@- place. The mouth of the outer shell is now "drawn tightly against the matrix. Disk 19 is removed and the surplus concrete isv stricken levelwith the top ofthe mold,

which is then covered with a flat sheet iron plate 31, having its edges bent down to allow the plate to fit snugly over the mold, in

orderto protect it againstr the weather. An .annular recess is provided in thisr plate to take in the upwardly projecting annular bead 28a, the purpose of which is fully explained in the applicaton above referred to.

When the concrete hasbecome suiiciently hard to allow the inner shell 7 to bek withdrawn, which` will be after about 12 hours, Y late 31 is removed, the distance-batten 11 is pulledout, cam-bar 17 is turned to the position shown in Fig. 6, allowingthe two n frames or jaws of the restoring andcol- ,y is now again put on, and the concretepipe with its cement lining allowed to set, which will take from siX to eight days. Then the cap or plate 31 is lifted o', the nuts of the bolts holding together the angle-irons on each side of slit 24 are unscrewed, and thel sides ofthe shell sprung apart sufficiently to allow it to be lifted off, by handles 23a v'secured to the outside of the shell near its top? Having thusdescribed my invention what I claim as new is the following:

' 1. In a mold for` making plastic articles,

a main shell, and aV perforated Vsurfacing shell removablydisposed within said main prising inner and outer concentric shells, and two perforated surfacing shells, one fitting near the inner main shell and one fitting near the outer main shell.

` 8. A mold for making plastic pipes comprising inner and outer concentric shells, two perforated surfacing shells, one fitting 2. A mold for making plastic pipes comnear the inner main shell and one tting f near the outer main shell, vand means carried by said surfacing shells for feeding cement into the mold.

-In testimony whereof .I afiX my signature in presence of two witnesses.

JULIUS Gr. ZWICKER. Witnesses:

G. A. GUENA, v EDWARDo ROMERO.

Copies of this patent may be obtained for five cents each, by addressing the. Commissioner of Patents. Washington, D. C. 

